DL 420 then AA 618 at O'Hare
Savannah → Chicago → Dallas-Fort Worth
Timetable, Chicago time
13:13DL 420 from Savannah at the gate
12:10AA 618 to Dallas-Fort Worth leaves the gate
22 h 57 apart on the timetable, overnight
AA 618 leaves 22 h 57 after DL 420 arrives on the timetable: more than half a day, so not a connection we count.